EP3352145A1 - Optisch detektierbare marker mit lumineszenten dotierungsmitteln sowie system und verfahren zum lesen solcher marker - Google Patents

Optisch detektierbare marker mit lumineszenten dotierungsmitteln sowie system und verfahren zum lesen solcher marker Download PDF

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Publication number
EP3352145A1
EP3352145A1 EP17152670.0A EP17152670A EP3352145A1 EP 3352145 A1 EP3352145 A1 EP 3352145A1 EP 17152670 A EP17152670 A EP 17152670A EP 3352145 A1 EP3352145 A1 EP 3352145A1
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EP
European Patent Office
Prior art keywords
luminescent
detectable marker
optically detectable
dopants
wavelength
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
EP17152670.0A
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English (en)
French (fr)
Inventor
Miguel Rafael Carro Temboury
Tom André Jos Vosch
Riikka Matleena Arppe
Thomas Just SØRENSEN
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Kobenhavns Universitet
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Kobenhavns Universitet
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kobenhavns Universitet filed Critical Kobenhavns Universitet
Priority to EP17152670.0A priority Critical patent/EP3352145A1/de
Priority to US16/478,573 priority patent/US11043058B2/en
Priority to PCT/EP2018/051452 priority patent/WO2018134405A1/en
Priority to ES18700608T priority patent/ES2950573T3/es
Priority to EP18700608.5A priority patent/EP3571678B1/de
Publication of EP3352145A1 publication Critical patent/EP3352145A1/de
Withdrawn legal-status Critical Current

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    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07D—HANDLING OF COINS OR VALUABLE PAPERS, e.g. TESTING, SORTING BY DENOMINATIONS, COUNTING, DISPENSING, CHANGING OR DEPOSITING
    • G07D7/00—Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency
    • G07D7/06—Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency using wave or particle radiation
    • G07D7/12—Visible light, infrared or ultraviolet radiation
    • G07D7/1205—Testing spectral properties
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/02—Use of particular materials as binders, particle coatings or suspension media therefor
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/77—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
    • C09K11/7766—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals containing two or more rare earth metals
    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07D—HANDLING OF COINS OR VALUABLE PAPERS, e.g. TESTING, SORTING BY DENOMINATIONS, COUNTING, DISPENSING, CHANGING OR DEPOSITING
    • G07D7/00—Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency
    • G07D7/20—Testing patterns thereon
    • G07D7/202—Testing patterns thereon using pattern matching

Definitions

  • the present invention relates to an optically detectable marker, a product provided with such an optically detectable marker as well as a system and method for reading out such optically detectable markers.
  • Anti-counterfeit tagging using reliable optical methods may provide the solution for addressing the billion dollar economic losses imposed by counterfeiting and may save lives if used to guarantee the authenticity of medicine.
  • US 2004/0112962 discloses security tags with randomly oriented particles embedded in a light transmitting matrix.
  • the read-out of the security tag is based on interpreting light reflected, refracted or diffracted by the particles in the matrix.
  • the intensity and colour variation stems from the host material onto which the security tag has been deposited, which makes the read-out dependent on the host material.
  • US 2004/0262547 discloses an optically detectable security marker for emitting light at a pre-selected wavelength.
  • the marker comprises a rare earth dopant and a carrier incorporating the rare earth dopant.
  • the interaction of the carrier and the dopant is such that the fluorescent fingerprint of the marker is different from that of the rare earth dopant.
  • the emission profile of the security marker may be detected and compared with a security profile. The system is thus encumbered with the aforementioned disadvantages.
  • US 2010/0102250 discloses a phosphor material based authentication system, in which a blend of at least two and preferably three or more phosphor materials are used as a photo-luminescent security marking, which is applied to or incorporated within an article to be authenticated.
  • the authenticity of the article can be authenticated by verification of the composition of the phosphor by exciting the marking and comparing one or more selected parameters of light emitted by the security marking with corresponding parameters of the characteristic emission spectrum of the authentic phosphor blend.
  • the authentication system is also encumbered with the aforementioned disadvantages.
  • US 2011/0164748 discloses a packaging film, which contains pigment particles randomly distributed in low surface-area density used for the authentication for products.
  • the positional coordinates, and optionally the colour values, of the pigment particles contained in the packaging film are determined from a digital image by means of a computer program and an identification code is calculated from the coordinate or colour values and stored in a database.
  • an identification code is calculated from the coordinate or colour values and stored in a database.
  • the invention provides an optically detectable marker comprising a matrix material, which is doped with a plurality of individual luminescent dopants and comprising at least a first luminescent dopant and a second luminescent dopant, wherein
  • the first luminescent dopants may be distributed in the matrix material so as to form a first spatial pattern and the second luminescent dopants may be distributed in the matrix material so as to form a second spatial pattern.
  • the patterns emerge, when the dopants are illuminated with light of the individual unique absorption band.
  • the patterns may be divided into individual areas or pixels in the marker. Accordingly, it is seen that each individual area or pixel may comprise two bits of information. If the marker for instance is divided into 60x60 pixels, the marker may provide 3 3600 different combinations (excluding "white" pixels). Since the dopants typically will have a random distribution in the matrix material, each marker will have a unique spatial pattern.
  • the markers may be used as security or anti-counterfeiting tags or the like and are impossible to clone, thereby providing a true physical unclonable function device (PUF device).
  • the spatial patterns may be recorded and stored in a database.
  • a later readout of the marker may be used to check the authenticity of the product by comparing the readout with the stored spatial patterns from the database.
  • the readout method has to be linked to the spatial patterns and thus include illumination that specifically targets the individual dopants.
  • the invention also provides an optically detectable marker, wherein the individual luminescent dopants further comprises a third luminescent dopant, wherein the third luminescent dopant comprises a third unique absorption band such that the third luminescent dopant may be excited by illumination of a third wavelength, different from the first wavelength, and wherein the third luminescent dopant is distributed in the matrix material so as to form a third spatial pattern in the matrix material, which third spatial pattern may be optically detected by illuminating the security tag by a light source illuminating light of the third wavelength.
  • the marker may provide 7 3600 different combinations (excluding "white” pixels).
  • the number of possible combinations may of course be expanded further by adding a fourth different dopants with unique absorption bands in order to provide additional spatial patterns by illumination.
  • the use of three (or even two) individual dopants are sufficient to provide a huge number of random patterns and thus a PUF device.
  • the addition of additional dopants may introduce crosstalk or other noise sources to the readout of the optically detectable marker.
  • the first spatial pattern and second spatial pattern are observable when the first dopants and second dopants are excited, respectively, and emits light.
  • the wavelength range observed or detected for the individual dopants may be the same.
  • the characteristics of excitation bands of the individual luminescent dopants are such that by illuminating the optically detectable marker, only a single luminescent dopant is excited and emits light.
  • the unique absorption band may be defined as a wavelength range, in which the intensity of emitted light from excitation of the targeted luminescent dopant due to illumination of light at the targeted wavelength is substantially higher than the intensity of emitted light from excitation of the luminescent dopants other than the targeted luminescent dopant.
  • the ratio between the intensity of emitted light from the targeted luminescent dopant and the intensity of emitted light from one of the other luminescent dopants may for instance defined to be at least 3:1 and preferably at least 7:1.
  • the ratio may advantageously be at least 10:1.
  • the ratio may even more advantageously be at least 25:1, 50:1, or 100:1.
  • the individual luminescent dopants are randomly distributed in the matrix material.
  • the randomly distributed dopants maybe accomplished during manufacture of the optical marker, where the dopants may be mixed into the matrix material.
  • the matrix material is a material chosen from the group of: PVA, PMMA, epoxy, glass, wood, synthetic polymers, biological polymers, plastics, inks, ceramics, lacquer, glue, resins, paper, nail polish, leather, inks, graphite, and chalk.
  • any suitable material may be used as a matrix material, as long as the dopants may be locked in the matrix material, such that the specific spatial patterns may be maintained.
  • the dopants may for instance be printed on surface, embedded, engraved or textured into the matrix material.
  • the individual luminescent dopants are contained in individual carriers that are embedded in the matrix material.
  • the individual carriers may for instance be a porous material, and the dopant thus "colour" the carrier.
  • the individual carriers may be provided as particles.
  • the individual carriers may carry one or more different dopants.
  • the individual carriers are microporous, mesoporous or macroporous structures.
  • the individual carriers are zeolites. Accordingly, the zeolite material, which is microporous, may function as a scaffold carrying the individual luminescent dopants.
  • the individual luminescent dopants may for instance be chosen from the group of: luminescent dyes, luminescent elements, quantum dots, rare earth dopants or lanthanides.
  • Lanthanides are particular advantageous and are not prone to bleaching.
  • the lanthanides are excited by light matching intrinsic lanthanide specific transitions.
  • the individual luminescent dopants includes lanthanides chosen from the group of: Ce, Nd, Sm, Ho, Pr, Dy, Eu, Tm, Yb, Tb, or Er.
  • the lanthanides may advantageously be chosen from the group of europium, terbium and dysprosium ions, e.g. Eu 3+ , Tb 3+ , and Dy 3+ . These ions inherently comprise individual absorption band, which are close to each other in wavelengths. This will add additional security to the marker, since the individual lanthanides cannot readily be individually targeted with a broadband light source but instead needs to be targeted with specific narrowband light sources.
  • the absorption bands of the individual absorption/excitation bands in principle may be spaced spectrally far apart, such as up to 1000 nm, or up to 500 nm.
  • the absorption/excitation bands may advantageously be close to each other. Therefore, according to an advantageous embodiment the first wavelength and the second wavelength are close to each other, preferably within 100 nm of each other and more preferably within 50 nm of each other.
  • neighboring unique absorption bands of the individual luminescent dopants are preferably located within 100 nm and more preferably within 50 nm of each other. This may also make it more likely that the emitted and detectable wavelengths are in the same range.
  • the dopants may advantageously have an average diameter of 0.1-100 ⁇ m, more advantageously 1-10 ⁇ m.
  • the carriers, such as zeolites may have an average diameter of 0.1-100 ⁇ m, ore advantageously 1-10 ⁇ m.
  • Average diameter means the average inner dimensions of the dopant or carrier.
  • the optical detectable marker may advantageously have a side dimension or average inner dimension of 10 ⁇ m to 10 mm.
  • the optical detectable marker may for instance be rectangular or square.
  • the spatial patterns may for instance be digitized into a pixel image having a side dimension of at least five pixel, e.g. being at least 5x5 pixels.
  • the digitized image may have a side dimension of at least 10 pixels, e.g. being 10 x 10 pixels or 10 x 20 pixel.
  • the invention provides a product provided with an optically detectable marker according to any of the aforementioned embodiments.
  • the optically detectable marker can be provided on the product in a number of ways.
  • the marker may for instance be provided as a thin film, such as a polymer film.
  • the film may be sealed so as to be scratch resistant.
  • the marker may also be provided as a dopants distributed in a glass matrix.
  • the marker may be glued on to product or imprinted. It can also be embedded in the product.
  • the individual dopants are advantageously embedded in the matrix with a spacing to the surface so as to make the marker scratch resistant. In general, the individual dopants or carriers carrying the dopants need to be locked in the matrix material so that the detectable spatial patterns are stable.
  • the invention provides a security system comprising:
  • the security system ensures that the contrast between the individual luminescent dopants is generated from the unique absorption bands. It is not necessary to discriminate the emitted light from the luminescent dopants, and in general, all emitted wavelengths are detected. More importantly, the emitted wavelengths from all individual luminescent dopants may be detected and recorded in the same wavelength range.
  • the security system further comprises a database of stored security tags.
  • the database may be stored locally or on an external server.
  • the stored security tags preferably comprise digitized images of the first spatial pattern and the second spatial pattern of optical detectable markers. The images may be recorded, when the optical detectable markers are manufactured or applied to a product, whereby the security tags may be used to establish the authenticity of the product.
  • the security system further comprises a comparison module, which is configured to compare detected spatial patterns or images with stored security tags.
  • the comparison module may provide a signal to indicate whether or not the optically detectable marker corresponds to a stored security tag.
  • the one or more light sources comprises a tunable light source, such as a tunable laser.
  • a tunable light source such as a tunable laser.
  • the system or light source may advantageously comprise a narrowband filter to ensure that only specific wavelengths and absorption bands are targeted.
  • Other embodiments could include a combination of a number of fixed wavelength lasers or light sources.
  • the system may further comprise a detector filter, e.g. a programmable filter.
  • the filter may for instance be utilized to observe specific emission wavelength ranges for the individual luminescent dopants. This may lower cross-talk or eliminate it entirely for detection of the first and the second spatial pattern.
  • the invention provides a method of reading out an optically detectable marker, wherein
  • Steps a) and b) may be repeated for each of the plurality of individual luminescent dopants.
  • the invention provides a readout method, where the individual spatial patterns formed by the individual luminescent dopants in the matrix material are read out separately by targeting the individual and unique absorption bands of the individual luminescent dopants.
  • the read out spatial patterns are run through a noise-reducing filtering process, e.g. comprising steps of:
  • the background noise corresponds to the normal measured counts of photons per time unit.
  • the background noise can be measured by measuring an output without illuminating the optical detectable marker.
  • Crosstalk can be reduced by comparing measured intensity level with a threshold level.
  • the threshold level may for instance be set according to the aforementioned ratios that can be used to define the unique absorption bands.
  • the whole system may for instance be calibrated or normalized in relation to a maximum read out intensity level.
  • background noise and cross talk can be further reduced by using pulsed excitation sources in combination with time-correlated single photon counting detection and photon arrival time based signal filtering and noise reduction.
  • the first spatial pattern detected in step b) and the second spatial pattern detected in step d) is compared to security tag stored in a database.
  • the method may additionally return a message or signal to indicate whether or not the detected spatial patterns correspond to a stored security tag.
  • the match level (e.g. number of pixels matching) between the detected spatial pattern and the stored security tag should be above 50% in order to avoid a random match. However, due to noise levels and other sources of errors, it is not practical to set the match level to a 100%. However, due to the nature of the PUCs, it is sufficient to set the match level to 55% or higher in order to correctly identify a tag.
  • the match level may for instance be set to at least 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or 95%.
  • an additional luminescent dopant to the optical detectable tag, which is not used for measuring a separate spatial pattern.
  • Such an additional tag can be used to add noise to a read out security tag, e.g. by being excited and emitting light if illuminated with the wrong wavelengths, e.g. when illuminated by a broadband (white) light source.
  • an additional luminescent dopant can be added to cover a time domain after excitation that is not used in the photon arrival time based signal filtering and noise reduction.
  • Fig. 1 illustrates a product 50 in form of a blister pack with medicine.
  • the product is provided with a serial tag that comprises an optically detectable marker 10 according to the invention.
  • an optically detectable marker 10 for medical products, it may save lives, if such markers 10 can be used to authenticate the origin and authenticity of the medicine.
  • Fig. 2 shows illustrates another authentic product 50 in form of a handbag and a counterfeit handbag 52.
  • the authentic product 50 has been provided with an optically detectable marker 10, which in an optical read-out method reveals a particular image or pattern.
  • the image or pattern from the optically detectable marker 10 can be used to authenticate the product 50, for instance by comparing the image with an image from a database.
  • the counterfeit handbag 52 instead comprises a fake optically detectable marker 12. If no matches of the fake marker 12 can be found in the database, it can be concluded that the product 52 is likely to be a counterfeit product.
  • the serial number e.g. as illustrated in Fig. 1 , to compare marker with a marker stored together with the serial number in the database.
  • the present invention in general relates to anti-counterfeit tagging using a reliable optical method to read out the tag and which cannot easily be copied or cloned.
  • Fig. 5 illustrates spatial patterns formed by individual luminescent dopants in an optically detectable marker 10 according to the invention as well as a combined image formed by the spatial patterns.
  • the optically detectably marker 10 is made of a matrix material, such as a polymer, which is doped with a plurality of different types of luminescent dopants, which are distributed, advantageously randomly, in the matrix material.
  • a matrix material such as a polymer
  • Each of the different types of luminescent dopants form separate spatial patterns in the optically detectable marker.
  • Each of the different types of luminescent dopants have a unique absorption band such that the luminescent dopants may be excited by illumination of light having a wavelength within the unique absorption band. Accordingly, it is possible to only excite one type of luminescent dopant at a time and a spatial pattern relating to the particular luminescent dopant type may be read out separately.
  • the detected spatial patterns may be digitized and divided into pixels.
  • a single pixel may contain more than 1 bit of information, which dramatically increases the number of possible unique tags.
  • each pixel may have three different values (excluding "white”).
  • the number of pixel may be even higher, e.g. at least having a side dimension of at least 5, 10, 15, 20, 25, 30, 60, or 100 pixels.
  • the images of course need not be square.
  • the pixels may also comprise a 3D matrix with X, Y and Z coordinates.
  • the luminescent dopant have to be targeted individually with a light source having wavelengths that substantially only excites the targeted luminescent dopant and substantially does not excite the other luminescent dopants. This adds a further security aspect to the markers.
  • Fig. 5 illustrates the principle above by use of images digitized images of the optically detectable marker 10 having three different types of luminescent dopants distributed in the matrix material of the optically detectable marker 10.
  • the example is illustrated as a 12x12 pixel image.
  • a first spatial pattern 20 is formed in the optically detectable marker 10 by first luminescent dopants 25 of a first type distributed in the matrix material of the optically detectable marker 10.
  • the first spatial pattern 20 emerges by targeting the unique absorption band of the first luminescent dopants 25 by illuminating the optically detectable marker 10 with light of a first wavelength.
  • the first luminescent dopants 25 are thereby excited and emits light, whereby the position of the luminescent dopants 25 may be detected and hence the first spatial pattern 20.
  • a second spatial pattern 30 is formed in the optically detectable marker 10 by second luminescent dopants 35 of a second type distributed in the matrix material of the optically detectable marker 10.
  • the second spatial pattern 30 emerges by targeting the unique absorption band of the second luminescent dopants 35 by illuminating the optically detectable marker 10 with light of a second wavelength.
  • the second luminescent dopants 35 are thereby excited and emits light, whereby the position of the luminescent dopants 35 may be detected and hence the second spatial pattern 30.
  • a third spatial pattern 40 is formed in the optically detectable marker 10 by third luminescent dopants 45 of a third type distributed in the matrix material of the optically detectable marker 10.
  • the third spatial pattern 40 emerges by targeting the unique absorption band of the third luminescent dopants 45 by illuminating the optically detectable marker 40 with light of a third wavelength.
  • the third luminescent dopants 45 are thereby excited and emits light, whereby the position of the luminescent dopants 45 may be detected and hence the third spatial pattern 40.
  • the three spatial patterns may form different channels in a combined image 48, similar to the three channels in an RGB image.
  • the combined image or the individual spatial images 20, 30, 40, or both may be stored in a database for later authentication.
  • Fig. 3 shows a security system 100 according to the invention.
  • the security system comprises an optical read-out system 110 for reading out the optically detectable marker 10 of the product 50.
  • the security system comprises a controller and a processor for processing the detected spatial patterns of the optically detectable marker.
  • the system may further comprise a database 180 of stored security tags.
  • the system may further comprise a comparison module, which is configured to compare detected spatial patterns or images with stored security tags stored in the database 180.
  • the database 180 may be implemented in the unit itself or it may implemented on an external server or cloud solution. It is also possible to attribute a serial number to each code, and the marker may be compared to a stored spatial patterns or images associated with the serial number.
  • the optical readout system 110 comprises one or more light sources 115.
  • the light source may for instance be a tunable laser, a broadband light source combined with a tunable filter, or different light sources emitting different wavelengths.
  • the optical readout system 110 further comprises a detection system for reading out a spatial pattern associated with the individual luminescent dopants of the optically detectable marker 10.
  • the detection system may comprise an imaging system including for instance a first lens 125 and a second lens 130, a detector array 140, such as a CCD , CMOS array, APD, PMT or any other photon detection equipment, and optionally a tunable filter 135.
  • the one or more light source 115 emits light that is sent to a beam splitter and then on to the optically detectable marker 10 via the first lens 125.
  • the targeted luminescent dopants are excited and emits light, which is sent via the first lens, through the beam splitter 120 and onto the detector array 140 via the second lens 130.
  • the optical readout system 110 may further comprise a tunable filter 135, which can be used to limit crosstalk between light emitted from different types of luminescent dopants.
  • optical readout system 110 may be implemented in a number of different ways, but it is important that the optical readout system is configured to target and excite the individual luminescent dopants separately and detect the associated spatial pattern in the optically detectable marker 10.
  • the individual luminescent dopants may be directly distributed in the matrix material or be contained in individual carriers that are embedded in the matrix material.
  • the individual carriers may for instance be a porous material, and the dopant thus "colour" the carrier.
  • the individual carriers may be provided as particles.
  • the individual carriers may carry one or more different dopants.
  • the individual carriers are zeolites. Accordingly, the zeolite material, which is microporous, may function as a scaffold carrying the individual luminescent dopants.
  • the individual luminescent dopants may for instance be chosen from the group of: luminescent dyes, luminescent elements, quantum dots, rare earth dopants or lanthanides.
  • lanthanides are particular advantageous, since they are stable and not prone to bleaching.
  • the lanthanides may advantageously be chosen from the group of europium, terbium and dysprosium ions, e.g Eu 3+ , Tb 3+ , and Dy 3+ . These ions inherently comprise individual absorption bands, which are close to each other in wavelengths. This will add additional security to the marker, since the individual lanthanides cannot readily be individually targeted with a broadband light source but instead needs to be targeted with specific narrowband light sources.
  • the optically detectable marker 10 may have different sizes and that the resolution of the image may be varied.
  • Fig. 6A illustrates an image where single dopants or carriers only fill one or a few pixels.
  • the optically detectable marker 10 may also be observed at a higher resolution, wherein the shape of the dopants or carriers may be observed. In the latter case, the optically detectable marker 10 may physically be smaller, e.g. as small as for instance 10 x 10 ⁇ m.
  • the dopants may advantageously have an average diameter of 0.1-100 ⁇ m, more advantageously 1-10 ⁇ m.
  • the carriers, such as zeolites may have an average diameter of 0.1-100 ⁇ m, more advantageously 1-10 ⁇ m.
  • Average diameter means the average inner dimensions of the dopant or carrier.
  • the optical detectable marker may advantageously have a side dimension or inner dimension of 10 ⁇ m to 10 mm.
  • the optical detectable marker may for instance be rectangular or square.
  • the spatial patterns may for instance be digitized into a pixel image having a side dimension of at least five pixel, e.g. being at least 5x5 pixels.
  • the digitized image may have a side dimension of at least 10 pixels, e.g. 10 x 10 pixels or 10 x 20 pixels.
  • the relative size between the side dimension of the marker and the average diameter of the dopants may advantageously be at least 2:1, more advantageously at least 3:1 and even more advantageously at least 5:1.
  • the invention for the excitation-selected imaging has been demonstrated by the inventors based on lanthanide-doped zeolites.
  • the uniquely narrow absorption peaks of lanthanides enable to use three, energetically closely spaced excitation wavelengths for the selective excitation of Eu 3+ , Tb 3+ , and Dy 3+ .
  • Figs. 7A and 7B show absorption and normalized excitation spectra for the three lanthanides, respectively.
  • Tb 3+ has a unique absorption band 72 with an absorption peak at 488 nm.
  • Eu 3+ has a unique absorption band 70 with a very narrow absorption peak at 465 nm and another at 416 nm.
  • Dy 3+ has three absorption peaks at 425 nm, 450 nm, and 475 nm, from which the unique absorption 74 with the best absorptivity is at 450 nm. The combination of the three unique absorption bands gives minimal crosstalk between the three lanthanides.
  • Dy 3+ absorption peaks are the broadest and, therefore, most excitation crosstalk is expected from Dy 3+ -doped zeolites.
  • Eu 3+ has a minor absorption peak at 488 nm, which can cause some crosstalk from Eu 3+ -doped zeolites.
  • the crosstalk can be minimized or eliminated by comparing the measured intensities to a threshold intensity 80.
  • the different lanthanides also emit light with different spectra. By detecting only specific wavelength ranges relevant for the different lanthanides, it may be possible to eliminate crosstalk entirely. Additionally photon arrival times after pulsed excitation could also be used to minimize or eliminate crosstalk. This may for instance be carried out by use of the tunable filter 135 in the optical read-out system 110.
  • Fig. 8 shows the steps in a method of reading out an optically detectable marker according to the invention.
  • the optical detectable marker 10 is first illuminated with a light of wavelength ⁇ 1 in step 220, and the associated first spatial pattern P 1 is detected in step 230.
  • i is incremented.
  • i is compared to N, which is the number of individual luminescent dopants used in the optically detectable marker. Since N according to the invention is at least 2, steps 220-250 are repeated including first illuminating the optically detectable marker 10 with a light of wavelength ⁇ 2 detecting the associated second spatial pattern P 2 .
  • the loop is continued until all luminescent dopants have been separately targeted and excited, and the associated spatial pattern has been detected.
  • step 260 the method then continues to an optional noise filtering step 260, where for instance background noise may be subtracted. It is recognized that this step may also be placed in the loop, e.g. between steps 230 and 240.
  • the image is then in step 270 digitized, e.g. by comparing the measured intensities with a threshold level. This may further minimize crosstalk.
  • step 280 the image may be compared with an image stored in a database of security tags in order to authenticate the product 50. It is recognized that various image recognition methods or similar methods may be used to authenticate the product 50, such as for example a simple cross-correlation function. In general, more than 50% of the image should match the stored tag, preferably at least 55%.

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EP17152670.0A 2017-01-23 2017-01-23 Optisch detektierbare marker mit lumineszenten dotierungsmitteln sowie system und verfahren zum lesen solcher marker Withdrawn EP3352145A1 (de)

Priority Applications (5)

Application Number Priority Date Filing Date Title
EP17152670.0A EP3352145A1 (de) 2017-01-23 2017-01-23 Optisch detektierbare marker mit lumineszenten dotierungsmitteln sowie system und verfahren zum lesen solcher marker
US16/478,573 US11043058B2 (en) 2017-01-23 2018-01-22 Optically detectable marker including luminescent dopants and system and method for reading such markers
PCT/EP2018/051452 WO2018134405A1 (en) 2017-01-23 2018-01-22 An optically detectable marker including luminescent dopants and system and method for reading such markers
ES18700608T ES2950573T3 (es) 2017-01-23 2018-01-22 Un marcador ópticamente detectable que incluye dopantes luminiscentes y sistema y procedimiento para leer dichos marcadores
EP18700608.5A EP3571678B1 (de) 2017-01-23 2018-01-22 Optisch detektierbare marker mit lumineszenten dotierungsmitteln sowie system und verfahren zum lesen solcher marker

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021058970A1 (en) * 2019-09-24 2021-04-01 Chromatwist Limited Polymers
EP3908814A4 (de) * 2019-01-08 2022-10-12 ChemImage Corporation System und verfahren zur verdeckten identifizierung
GB2619067A (en) * 2022-05-26 2023-11-29 Quantum Base Ltd Optically readable physical unclonable functions

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11713268B2 (en) 2019-05-30 2023-08-01 Owens-Brockway Glass Container Inc. Period-coded containers with a traceable material composition

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040112962A1 (en) 2000-12-20 2004-06-17 Farrall Andrew John Security, identificaiton and verification systems
US20040262547A1 (en) 2003-06-26 2004-12-30 Ncr Corporation Security labelling
US20060180792A1 (en) * 2003-06-26 2006-08-17 Prime Technology Llc Security marker having overt and covert security features
US20100102250A1 (en) 2008-10-23 2010-04-29 Intematix Corporation Phosphor based authentication system
US20110164748A1 (en) 2008-07-11 2011-07-07 Christian Kohlert Packaging film for product authentication, authentication method and system
DE102014016858A1 (de) * 2014-02-19 2015-08-20 Giesecke & Devrient Gmbh Sicherheitsmerkmal und Verwendung desselben, Wertdokument und Verfahren zur Prüfung der Echtheit desselben
US20150324677A1 (en) * 2014-05-07 2015-11-12 Vitaly Talyansky Multi-Layer Optical Barcode with Security Features

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060161788A1 (en) * 2004-11-01 2006-07-20 Ken Turpin Full color spectrum object authentication methods and systems
US20090008924A1 (en) * 2005-05-11 2009-01-08 Koninklijke Philips Electronics, N.V. Authenticating banknotes or other physical objects
US7995196B1 (en) * 2008-04-23 2011-08-09 Tracer Detection Technology Corp. Authentication method and system
JP5541583B2 (ja) * 2010-08-04 2014-07-09 大日本印刷株式会社 発光媒体および発光媒体の確認方法
WO2015189764A1 (en) * 2014-06-09 2015-12-17 Ashish Anand Automated verification of optical randomness in security label
KR101699330B1 (ko) * 2015-08-19 2017-01-24 재단법인대구경북과학기술원 랜덤매질을 이용한 복제 방지 시스템 및 방법
EP3390067B9 (de) * 2015-12-17 2021-09-01 Sicpa Holding Sa Sicherheitselement, sicherheitsanordnung, verfahren zur herstellung davon und authentifizierungsverfahren damit
JP6707926B2 (ja) * 2016-03-16 2020-06-10 凸版印刷株式会社 識別システム、識別方法及びプログラム
US10535212B2 (en) * 2016-12-19 2020-01-14 Sensor Electronic Technology, Inc. Ultraviolet fluorescent authentication

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040112962A1 (en) 2000-12-20 2004-06-17 Farrall Andrew John Security, identificaiton and verification systems
US20040262547A1 (en) 2003-06-26 2004-12-30 Ncr Corporation Security labelling
US20060180792A1 (en) * 2003-06-26 2006-08-17 Prime Technology Llc Security marker having overt and covert security features
US20110164748A1 (en) 2008-07-11 2011-07-07 Christian Kohlert Packaging film for product authentication, authentication method and system
US20100102250A1 (en) 2008-10-23 2010-04-29 Intematix Corporation Phosphor based authentication system
DE102014016858A1 (de) * 2014-02-19 2015-08-20 Giesecke & Devrient Gmbh Sicherheitsmerkmal und Verwendung desselben, Wertdokument und Verfahren zur Prüfung der Echtheit desselben
US20150324677A1 (en) * 2014-05-07 2015-11-12 Vitaly Talyansky Multi-Layer Optical Barcode with Security Features

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3908814A4 (de) * 2019-01-08 2022-10-12 ChemImage Corporation System und verfahren zur verdeckten identifizierung
US11499912B2 (en) 2019-01-08 2022-11-15 Chemimage Corporation Systems and methods of covert identification
WO2021058970A1 (en) * 2019-09-24 2021-04-01 Chromatwist Limited Polymers
GB2619067A (en) * 2022-05-26 2023-11-29 Quantum Base Ltd Optically readable physical unclonable functions

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Publication number Publication date
EP3571678A1 (de) 2019-11-27
EP3571678C0 (de) 2023-07-05
ES2950573T3 (es) 2023-10-11
US11043058B2 (en) 2021-06-22
US20200051358A1 (en) 2020-02-13
WO2018134405A1 (en) 2018-07-26
EP3571678B1 (de) 2023-07-05

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